Railway track switch controlling apparatus



N 1950 J. .1. COAKLEY 2,961,206

RAILWAY TRACK SWITCH CONTROLLING APPARATUS Filed July 2, 1957 INVENTOR.Q James J. Coakleg.

Hm awwozawzz Unitfid States Patent RAILWAY TRACK SWITCH CONTROLLINGAPPARATUS James J. Coakley, Elizabeth, NJ., assignor to Westinghouse AirBrake Company, Wilmerding, Pa, a corporation of Pennsylvania Filed July2, 1957, Ser. No. 669,515

'7 Claims. (Cl. 246-258) My invention relates to railway track switchcontrolling apparatus of a type wherein the operations of a railwaytrack switch are at times controlled from a point remote from the switchand are at other times controlled from a point adjacent the switch.

One object of my invention is the provision for an alarm indication atthe control point remote from the switch to indicate when the railwayswitch points have failed to complete a movement from one position tothe other.

Another object of my invention is to provide means for controlling arailway switch from a point adjacent the switch in such manner that,once a movement of the switch has been initiated, it will either attemptto continue the movement or will attempt to return to its formerposition.

Other objects and characteristic features of my invention will becomeapparent as the description proceeds.

The accompanying drawing is a diagrammatic view showing one form ofapparatus embodying my invention.

Referring to the drawing, the reference character T refers to a sectionof railway track provided with a track circuit whose limits are definedby insulated points I, and including a suitable source of track circuitcurrent here shown as a battery TB connected across the rails adjacentone end of the section, and a track relay TR connected across the railsadjacent the other end of the section. The track circuit as shown in thedrawing is the normally energized type, that is, the track relay isenergized when the track section is unoccupied by a train, but it is tobe understood that any type of track circuit may be employed.

Located in the track section T is a switch SW which is moved from normalto reverse positions and vice versa by some suitable device such, forexample, as a fluid pressure operated switch mechanism M which isequipped with normal and reverse control magnets designated by thereference characters N and R, respectively.

As shown in the drawing the switch occupies its normal position. If thereverse magnet R is now energized, fluid pressure will be supplied tomechanism M to operate switch SW to its reverse position. If, when theswitch occupies its reverse position, magnet N is energized, fluidpressure will be supplied to mechanism M to restore switch SW to itsnormal position.

Connected with switch SW is a circuit controller SWC comprising twocontacts In and Ir, two contacts 2n and Zr and two contacts 321 and Sr.Contacts 1n and Ir are closed when and only when the switch SW occupiesits normal or reverse positions, respectively. Either contact 2n or 2rdepending on whether the switch SW is nearer to its normal or reversepositions, respectively, is closed at all times except when the switchis in its exact midstroke position. Contacts 311 and 3r are closed oropen in accordance with the position of switch SW precisely as contacts2n and Zr, respectively, are closed or open;

their normal position, switch SW occupies its normalpo- The magnets Nand R of the switchmechanisnf 'M are controlled by the circuitcontroller SWC, by the track relay TR, by a first manually operablecontrol lever L1 and by a second manually operable control lever L2. Athird manually operable control lever L3 is used to select the controlof the magnets between lever L1 or lever L2 as desired.

Lever L1 is capable of assuming a normal position n and a reverseposition r, and is equipped with a plurality of contacts designated 4through 9 which are shown as circles with a reference character thereincorresponding to the lever position in which the contact will be closed.For example, contact 4 is closed only in the n position of lever L1,while contact 5 is closed only in the r position of lever L1. It shouldalso be pointed out at this time that the contacts of lever L1 are of aquick acting or snap type in order that a minimum of time will beconsumed between the opening of the normal contacts and the closing ofthe reverse contacts or vice versa. Contacts of this type are inwidespread use, and since these contacts by themselves form no part ofmy present invention, their detailed construction is not shown in thedrawing. The expediency of such contacts will be fully brought out laterin this description.

Lever L3 is also capable of assuming a normal position n and a reverseposition r and is equipped with a plurality of contacts designated 11through 14 which are also shown as circles with a reference charactertherein corresponding to the lever position in which the contact will beclosed.

Lever L2 is capable of assuming a normal position 11, a reverse positionr and a center position 0. This lever is mechanically biased to thecenter position c in such a manner that any time it is manually operatedto either the n or r position and then released, it will automaticallyreturn to the center position 0. This lever is equipped with a pluralityof contacts 16 through 19 which are shown as circles with a referencecharacter therein corresponding to the lever position in which thecontact will be closed.

Lever L1 is located at a point remote from the switch and lever L2 islocated adjacent the switch. Lever L3 may be located either at theremote control point or at the switch location, but, for purposes ofthis description, is presumably located at the point remote from theswitch.

An indication relay designated by the reference character KR and havinga slow release feature is also located at the remote control point. Thisrelay is normally energized and is shown in the drawing as having twodistinctly separate windings designated X and Y, the energization ofeither winding being operable to pick up the relay and retain it in thatposition. The slow release feature of the relay is effective upon theenergization of either winding. This KR relay is used to control analarm indication in the event the switch SW fails to complete itsmovement from one position to the other.

The apparatus also includes three indication lamps NWKE, RWKE and KRE,all located at the remote control point, and asymmetric units S1, S2 andS3, all lo cated at the switch location.

It should be pointed out at this time that a suitable source of controlcurrent designated by the reference character LB is provided, thiscurrent source being arranged in such a manner that a center tap isprovided. Each half of the center tapped source is preferably a batteryof proper voltage and capacity and its positive and negative terminalsare identified by reference characters B and 0, respectively. The centertap or common te.- minal is designated by the reference character C.

As shown in the drawing, all apparatus is in its normal position. Thatis to say, levers Ll, LZand L3 occupy sition, and track section T isunoccupiedby a train so that track relay TR is energized. Under theseconditions, magnet N is energized by a circuit which may be traced frombattery terminal B through normal contact 4 of lever L1, front contact aof relay TR, normal contact 11 of lever L3, the winding of magnet N, andasymmet ic unit S2 in its low resistance direction to battery terminalC. The energization of magnet N by the circuit thus traced causes fluidpressure to be supplied to switch mechanism M to hold the switch SW inits normalposition.

, Also under these conditions anin'dication circuit is completed forillumination of the normal switch indication lamp NWKE. This circuit maybe traced from battery terminal C through asymmetric unit S3. in the lowresistance direction, normal contact In of circuit controller SWC,normal contact 12 of lever L3, front contact b of relay TR, normalcontact 6 of lever L1, and the filament of indication lamp NWKE tobattery terminalO. Lamp NWKEis thusilluminated and indicates that theswitch'and lever L1 both occupy their normal positions and track sectionT is unoccupied by a train.

Under the above conditions a circuit is also completed retaining relayKR in its normally energized condition. This circuit may be traced frombattery terminal C through asymmetric unit S3 in its low resistancedirection, normal contact In of circuit controller SWC, normal contact12 of lever L3, the X winding of relay KR, and normal contact 8 of leverL1 to battery terminal 0. With relay KR in its energized position, itsback contact a is open and lamp KRE is dark indicating that switch SWis, in this instance, in its full normal position. The purpose of thisindication circuit will be more fully pointed out as this descriptionproceeds.

I shall now assume that all apparatus is in its normal position, asshown in the drawing, and the operator who manipulates lever L1 desiresto cause switch SW to move to its reverse position. The operator willmove lever L1 from its normal position it to its reverse position r,thereby opening contacts 4, 6 and 8 and closing contacts 5, 7

and 9. The opening of contacts 4, 6 and 8 interrupts respectively thepreviously traced circuits for the magnet N, the indication lamp NWKE,and winding X of relay KR, so that the magnet, lamp and relay all becomedeenergized. The closing of contact 7 completes a circuit for energizingreverse magnet R, which circuit may be traced from battery terminal Bthrough reverse contact 7 of lever L1, front contact of relay TR, normalcontact 12 of lever L3, the winding of magnet R, and through asymmetricunit S1 in its low resistance direction to battery terminal C. Magnet Rthus becomes energized and causes the switch SW to move to its reverseposition. This movement of the switch opens the normal contact In andcloses the reverse contact 1r of the circuit controller SWC. When thereverse contact 1r becomes closed, a circuit is completed for theillumination of the reverse indication lamp RWKE which may be tracedfrom battery terminal C through asymmetric unit S3 in its low resistancedirection, reverse contact 1r of circuit controller SWC, normal contact11 of lever L3, front contact a of relay TR, reverse contact 5 of leverL1, and the filament of lamp RWKE to battery terminal 0. Lamp RWKE isthus now' illuminated and indicates that'the switch and lever L1 areboth in their reverse positions and track section T is unoccupied by atrain.

Under the above described manipulation of lever L1 and consequentialopening of contact 8 of that lever, the previously traced energizingcircuit to winding X of relay relay KR. The energizing circuit forwinding Y of relay KR may be traced from battery terminal C throughasymmetric unit S3 in its low resistance direction, reverse contact 1rof circuit controller SWC, normal contact 11 of lever L3, winding Y ofrelay KR, and reverse contact 9 of lever L1 to battery terminal 0. It istherefore apparent that if switch SW completes its movement from normalto reverse in a predetermined period of time, no alarm indication willbe given asback contact a of relay KR will not close.

If, after the switch has moved-to its reverse position in the mannerdescribed, the operator desires to restore it to its normal position, hewill move lever L1 to its normal position. This manipulation of lever L1will open reverse contacts 5, 7 and 9 and close contacts 4, 6 and 8. Theopening of contacts 5, 7 and 9 will interrupt, respectively, the abovetraced circuits for indication lamp RWKE, the magnet R, and winding Y ofrelay KR. The closing of contact 4 will complete the previouslydescribed circuit for the normal magnet N and cause the switch to moveto its normal position. When the switch has completed this movement,normal contact In of circuit controller SWC will close and thepreviously traced circuit for the normal indication lamp NWKE will becompleted to indicatethat the switch SW and lever L1 are in their normalpositions. The previously traced circuit through Winding X of relay KRwill also be completed to retain that relay in its energized condition,the slow release feature of relay KR again bridging the period of timebetween the opening of the circuit to winding Y and the closing of thecircuit to winding X.

I shall now assume that the switch SWoccupies its normal position andthat a train enters the track section I T. The shunting of the trackcircuit by the train will KR is opened. However, this relay does notdrop out immediately due to its slow release feature. The snap action ofthe contacts of lever L1 and the fast action of the fluid pressureoperated switch mechanism operate to close an energizing circuit towinding Y of relay KR in a sufiiciently short period of time to retainthat relay picked up, the open circuit time between the opening of thecircuit to windingX'and closing of the circuit to winding Y beingbridged by the slow releasefeature of deenergize track relay TR, causingthat relay to open its front contacts a and b. The opening of thesecontacts will open thecontrol circuit to magnet N and the indicationcircuit to indication lampNWKE and extinguish that lamp. If at this timethe operator should move control lever L1 to its reverse position, theswitch will not move as the circuit to control magnet R will be open atfront contact b of relay TR. Furthermore, the circuit to indication lampRWKE will be open at contact a of relay TR and that lamp will remainextinguished.

The deenergization of relay TR, by the occupancy of track section T by atrain, also causes relay TR to close its back contact 0 and complete acircuit for energizing the normal control magnet. This circuit may betraced from battery terminal B through back contact c of relay TR,normal contact 2n of circuit controller SWC, winding of normal controlmagnet N, and asymmetric unit S2 in its low resistance direction tobattery terminal C. This circuit will thus retain magnet N energizedunder the.

described conditions and will insure that the switch Will remain in itsnormal position.

If a train enters track section T when the switch is in its reverseposition, the operation of the apparatus will be similar to that justdescribed when the switch occupies its normal position, except that theopening of contacts a and b will interrupt the reverse indicationcircuit to lamp RWKE and the energizing circuit for the reverse magnetR. Also the closing of back contact c of relay TR will complete aholding circuit to reverse magnet R which may be traced from batteryterminal B through back contact 0 of relay TR, reverse contact 2r of circuit controller SWC, winding of reverse magnet R, and asymmetric unit S1in its low resistance direction to has tery terminal C.

It is to be noted at this time that the deenergization of relay TR hasno effect on relay KR since no contacts of rfl 6 SW and also thecondition of occupancy of track section T, both lamps being extinguishedwhen that track section is occupied by a train. However, both of theselamps would also be extinguished if the switch SW would fail to completeits movement from one position to the other and stop somewhere betweenthe two positions due to some failure in the equipment, as the circuitto lamps NWKE and RWKE would be open at contacts In and Ir of circuitcontroller SWC, respectively. In the event of such an improper operationof switch SW, however, the energizing circuit to both windings of relayKR will also be open at contacts In and Ir of circuit controller SWCand, after the slow release feature of relay KR has no more effect, thatrelay will drop and give an alarm by the closing of a circuit forillumination of indication lamp KRE. This circuit may be traced frombattery terminal C through back contact a of relay KR, filament ofindication lamp KRE, and normal contact 14 of lever L3 to batteryterminal 0. Thus the illumination of lamp KRE serves to notify theoperator that the switch is not functioning properly, and there is noquestion in his mind whether lamps NWKE and RWKE are extinguished forthat reason or due to track section T being occupied by a train.

I shall now assume that track section T is unoccupied and it is desiredto control switch SW from the switch location, as may perhaps be thecase if the operator is on duty part time only and the trainmen operatethe switch the remainder of the time. As previously stated, lever L3 maybe located at either the remote or the local control points but, for thepurposes of this description, it is assumed to be located at the remotepoint. The ioperator, therefore, when desiring to turn over theoperation of the switch to anyone at the local control point or switchlocation, moves lever L3 from its normal to its reverse position.Assuming all apparatus to be in normal position, this manipulation willopen the control circuit to normal magnet N at normal contact 11 oflever L3 and the indication circuit to lamp NWKE at normal contact 12 oflever L3. The opening of contact 12 will extinguish lamp NWKE and alsodeenergize the X winding of relay KR, causing that relay to drop out. Iflever L1 and all apparatus are in correspondingly reverse positions atthe time the operator moves lever L3 as described, the control circuitfor reverse control magnet R and the indication circuit to lamp RWKEwould be opened at contacts 12 and 11, respectively, of lever L3. Theenergizing circuit to the Y winding of relay KR would also be opened atcontact 11 of lever L3. The dropping out of relay KR in either instancedoes not illuminate indication lamp KRE as its previously tracedenergizing circuit is opened at normal contact 14 of lever L3. All theindication lamps are, therefore,

extinguished and relay KR is deenergized when the operator moves leverL3 from its normal to its reverse position.

If switch SW is in its normal position, when lever L3 is moved reverseto transfer the control of the switch to the local control point, acircuit is completed to the normal control magnet N for retaining switchSW in its normal position. This circuit may be traced from batteryterminal B through front contact c of relay TR, reverse contact 13 oflever L3, normal contact 3n of circuit controller SWC, center contact 18of lever L2, winding of normal magnet N, and asymmetric unit S2 in itslow resistance direction to battery terminal C. If switch SW is in itsreverse position when the transfer of control is made, a holding circuitto reverse control magnet R is established which may be traced frombattery terminal B, through front contact of relay TR, reverse contact13 of lever L3, reverse contact 3r of circuit controller SWC, centercontact 16 of lever L2, winding of reverse magnet R, and asymmetric unitS1 in its low resistance direction to battery terminal C. Thesedescribed holding circuits will be maintained, depending on whether theames 3 switch is normal or reverse, as long as lever L2 remains in itscenter position 0. As previously pointed out, lever L2 is mechanicallybiased to its center position and will remain in that position untiloperated or will return to that position it moved therefrom and thenreleased.

The completion of the movement of lever L3 to its reverse positioncompletes the transfer of control of switch SW from the remote controlpoint to the local control point. If a trainman or other person desiresto cause the switch to move to its reverse position (the switch beingassumed to be in the normal position when the control transfer wasmade), lever L2 is moved to its reverse position and held there untilthe switch has completed its movement at least past its exact midstrokeposition. This movement of lever L2 will open, at center contact 18 oflever L2, the above traced holding circuit for the normal magnet N ofthe switch SW and close a control circuit to reverse magnet R of theswitch. This control circuit may be traced from battery terminal Bthrough front contact c of relay TR, reverse contact 13 of lever L3,reverse contact 19 of lever L2, winding of reverse control magnet R, andasymmetric unit S1 in its low resistance direction to battery terminalC. The energization of control magnet R will cause the switch to move toits reverse position. If the lever L2 is allowed to return to its centerposition 0 before the switch has passed its midstroke position, theabove described holding circuit to the normal magnet N will bereestablished, the normal magnet energized, and the switch will returnto its normal position.

If the switch SW was in its reverse position when the control transferwas made from the remote point to the local point and it is desired tocause the switch to move to its normal position, lever L2 is operated toits normal position .and held there until the switch has completed itsmovement at least past its exact midstroke position. This operation oflever L2 will open, at center contact 16 of lever L2, the previouslytraced holding circuit to reverse control magnet R and close a circuitfor energization of normal control magnet N. This circuit may be tracedfrom battery terminal B through front contact c of relay TR, reversecontact 13 of lever L3, normal contact 17 of lever L2, winding ofcontrol magnet N, and asymmetric unit S2 to battery terminal C Theresultant energization of control magnet N will cause switch SW to moveto its normal position. If lever L2 is allowed to return to its centerposition 0 before the switch has passed its midstroke position, thepreviously described holding circuit to reverse control magnet R will bereestablished, the reverse magnet energized, and the switch will returnto its reverse position.

If a movement of the switch SW from one position to the other isinitiated by the moving of lever L2 and the lever is held in theposition to which moved until the switch has merely passed its midstrokeposition and then the lever is released, the return of the lever to itscenter position c will establish the holding circuit for the newposition of the switch and cause continuation of the movement of theswitch to the new position.

I will now assume that the control of switch SW has been transferredfrom the remote control point to the local control point and a trainoccupies track section T. Under these conditions the circuit forenergization of control magnet N or R is open at front contact 0 oftrack relay TR and the previously described holding circuit to controlmagnet N or R is closed at back contact 0 of relay TR. Tt is thusapparent that the holding circuit to the control magnet N or R duringoccupancy of track section T operates identically whether the remotepoint or the local point is, at that time, the control point.

I will now assume that the switch SW is being operated from the localpoint or switch location and it is desired to transfer the control backto the remote control point. I will also assume that the switch was lastpositioned normal and remains so, and that the lever L1 is also-in itsnormal position. The operator moves lever L3 from its reverse positionto its normal position and reestablishes the firsttraced energizingcircuits for normal control magnet N,'indication lamp NWKE, and windingX of relay KR. The circuit for control of the magnets by lever L2 isopened at reverse contact 13 of lever L3. All the apparatus isthus'again in its normal condition.

I will now assume that, at the time the transfer is made, lever L1 is inits normal position and switch SW is in its reverse position. Thecircuit for control of the magnets by lever L2 will again be opened atreverse contact 13 of lever L3, and the closing of normal contacts 11and 12 of lever L3 will close the circuit for energizing normal magnet Nand cause the switch to move to its normal position. Upon completion ofthe movement of the switch, lever L1 and the switch will be inagreement, the indication light NWKE will be illuminated, and relay KRwill pick up and extinguish indication lamp KRE which was momentarilyilluminated when normal contact 14 of lever 13 closed upon the return ofthe lever to its normal position. All apparatus is again in its normalcondition.

If lever L1 is in its reverse position when the operator again assumescontrol of switch SW by the return of lever L3 to its normal position,and if switch SW is also in its reverse position at this time, nounusual action will result and all apparatus will immediately revert tothe condition in which it would be if the operator had retained controlof the switch, similarly as described above when lever L1 and the switchSW were both in their normal positions and the operator reassumed con-However, if lever L1 is in its reverse position and switch SW is in thenormal position when the operator returns lever L3 to its normalposition, reverse control magnet R will be energized upon the closing ofnormal contact 12 of lever L3 and switch SW will move to its reverseposition. Upon completion of the movement of the switch, lever L1 andthe switch will be in agreement, the indication light RWKE will beenergized and relay KR Will pick up. Indication light KRE would bemomentarily illuminated when normal contact 14 of lever L3 closed uponreturn of lever L3 to its normal position but the light would beextinguished when relay KR picked up and opened back contact a in thepreviously described energizing circuit to lamp KRE. All apparatus wouldthen be in its proper condition.

One advantage of the apparatus arrangement of my invention is that leverL2 being mechanically biased to a neutral or center position,'this levercan not be left in a position which is out of correspondence with theposition of the switch. Therefore, when the operator reverses lever L3to transfer control of the switch to lever L2, there is no danger oflever L2 being in a position out of correspondence with the position ofthe switch and thus inadvertently causing an unintentional movement ofthe switch which may be dangerous to trainmen or other persons at theswitch location.

Another advantage of my invention is the provision of the alarmindication KRE giving notice to the operator that the switch has notoperated properly to its full normal or full reverse position. Thisadditional indication isiprovided over the same conductors used forcontrol and switch position indication. While this alarm indication isshown in the drawing as a normally dark indication lamp, it is to beunderstood that a whistle, hell or other audible means could be used inplace of or in conjunction with the indication lamp.

Although I have herein shown and described only one form of apparatusembodying my invention, it is to be understood that various changes andmodifications may be made therein within the scope of the appendedclaims without departing fromthe spirit and scope of my invention.

8 I Having thus described my invention, what I claim is: 1. Incombination, a railway track switch, a mechanism connected to saidswitch for moving the switch, a normal and a reverse control magnet forcontrolling said mechanism to move said switch to normal and reversepositions respectively according as the normal or reverse control magnetis energized, a first control lever having normal and reverse positions;a second control lever having normal, center and reverse positions, saidlever being biased to its center position; a third control lever havingnormal and reverse positions, means con: trolled by said first and thirdcontrol levers for energizing said normal control magnet when said firstcontrol lever occupies its normal position and said third control leveroccupies its normal position, means controlled by said first and thirdcontrol'levers for energizing said reverse control magent when saidfirst control lever occupies its reverse position and said third controllever occupies its normal position, means controlled by said second andthird control levers for energizing said normal control magnet when saidthird control lever occupies its reverse position and said secondcontrol lever occupies its normal position, means controlled by saidsecond and third control levers for energizing said reverse controlmagnet when said third control lever occupies its reverse position andsaid second control lever occupies its reverse position; and meanscontrolled by said second and third control levers for energizing saidnormal or reverse control magnet according as said switch occupies itsnormal or reverse position respectively, when said third control leveroccupies its reverse position and said second control lever occupies itscenter position.

2. In combination, a railway track switch, a mechanism connected to saidswitch for moving the switch, a normal and a reverse control magnet forcontrolling said mechanism to move said switch to normal and reversepositions respectively according as the normal or reverse control magnetis energized, a first control lever having normal and reverse positions;a second control lever having normal, center and reverse positions, saidcontrol lever being biased to said center position; a third controllever having first and second positions, a first means for energizingsaid normal control magnet efiective when said first and third controllevers occupy their normal position, a second means for energizing saidnormal control magnet effective when said third control lever occupiesits reverse position and said second control lever occupies its normalposition; a third means for energizing said normal control magnetetfective when said third lever occupies its reverse position, saidsecond control lever occupies its center position and said switchoccupies a position between midstroke position and normal position, ornormal position; a first means for energizing said reverse controlmagnet effective when said third control lever occupiesits normalposition and said first control lever occupies its reverse position, asecond means for energizing said reverse control magnet efii'ective whensaid third control lever occupies its reverse position and said secondcontrol lever occupies its reverse position; and a third means forenergizing said reverse control magnet eiiective when said third controllever occupies its reverse position; said second control lever occupiesits center position and said switch occupies a position betweenmidstroke position and reverse position, or reverse position.

31in combination, a section of railway track, a track circuit for saidsection of railway track including a source of track circuit energy anda track relay, a railway track switch located within said section ofrailway track and having normal and reverse positions, a control leverhaving normal and reverse positions, an indication relay;

a first, second and third indication means; means effective forenergizing said first indication means when said track relay is in itsnormal condition, and said control lever and said switch occupy theirnormal positions;

means efi'ective for energizing said second indication means when saidtrack relay is in its normal condition, and said control lever and saidswitch are in their reverse positions; means effective for energizingsaid indi cation relay only when said control lever and said switch arein corresponding normal or reverse positions; and means effective forenergizing said third indication means when said indication relay isdeenergized.

4. In combination, a section of railway track, a track circuit for saidsection of railway track including a source of track circuit current anda track relay, a railway track switch located within said section ofrailway track and having normal and reverse positions, a mechanismconnected to said switch for moving the switch, a normal and a reversecontrol magnet for controlling said mechanism to move said switch tosaid normal or reverse positions respectively according as said normalor reverse control magnet is energized, a first control lever havingnormal and reverse positions; a second control lever having normal,reverse and center positions, said control lever being biased to itscenter position; a third control lever having normal and reversepositions; a first, second and third indication device; means effectivewhen said first control lever occupies its normal position, said thirdcontrol lever occupies its normal position and said track relay is inits normal condition for energizing said normal control magnet; meanseffective when said first control lever occupies its normal position,said third control lever occupies its normal position, said switchoccupies its normal position and said track relay is in its normalcondition for energizing said first indication device; means effectivewhen said first control lever occupies its reverse position, said thirdcontrol lever occupies its normal position and said track relay is inits normal condition for energizing said reverse control magnet; meanseffective when said first control lever occupies its reverse position,said third control lever occupies its normal position, said switchoccupies its reverse position and said track relay is in its normalcondition for energizing said second indication device; an indicationrelay; means effective when said third control lever occupies its normalposition and said first control lever and said switch occupycorresponding normal or reverse positions for energizing said indicationrelay; means efiective for energizing said third indication device whensaid indication relay is deenergized; means effective when said thirdcontrol lever occupies its reverse position, said second control leveroccupies its normal position and said track relay is in its normalcondition for energizing said normal control magnet; means efiectivewhen said third control lever occupies its reverse position, said secondcontrol lever occupies its reverse position and said track relay is inits normal condition for energizing said reverse control magnet; andmeans efiective when said third control lever occupies its reverseposition, said second control lever occupies its center position andsaid track relay is in its normal condition for energizing said normalor reverse control magnet according as said switch occupies its normalor reverse position respectively.

5. In railway track switch controlling apparatus including a mechanismfor moving said switch, the combination comprising, a first controllever, a second control lever biased to a preselected position, a thirdcontrol lever, means controlled by said third control lever forconnecting said mechanism to be selectively controlled by said first orsecond control lever according as the third lever occupies a first orsecond position respectively, and means controlled by said switch andsaid second lever in its preselected position for controlling saidmechanism to maintain the switch in its established position when themechanism is connected to be controlled by the second lever.

6. In railway track switch controlling apparatus including a mechanismfor moving said switch to its normal or reverse positions, thecombination comprising, a first control lever having normal and reversepositions; a second control lever having normal, center, and reversepositions, said lever being biased to its center position; a thirdcontrol lever having normal and reverse positions, means controlled bysaid third lever in its normal position and said first lever forcontrolling said mechanism to move said switch to its normal or reverseposition respectively according as the first lever occupies its normalor reverse position; and means controlled by said third lever in itsreverse position and said second lever for controlling said mechanism tomove said switch to its normal or reverse position respectivelyaccording as the second lever occupies its normal or reverse position,and controlling the mechanism to maintain the switch in its normal orreverse position when the second lever occupies its center position.

7. In combination, a railway track switch, a mechanism for moving saidswitch to normal or reverse positions, a normal and a reverse controlmagnet for controlling said mechanism to move said switch to its normalor reverse position according as the normal or reverse magnetrespectively is energized, a first control lever having normal andreverse positions; a second control lever having normal, center andreverse positions, said lever being biased to its center position; athird control lever having normal and reverse positions, meanscontrolled by said third control lever in its normal position and bysaid first control lever for energizing said normal or reverse controlmagne-t according as the first lever occupies its normal or reverseposition respectively, means controlled by said third control lever inits reverse position and by said second control lever for energizingsaid normal or reverse control magnet according as the second leveroccupies its normal or reverse position respectively; and meanscontrolled by said third control lever in its reverse position, by saidswitch, and by said second control lever in its center position forenergizing said normal or reverse control magnet, according as theswitch is nearer its normal or reverse position respectively.

References Cited in the file of this patent UNITED STATES PATENTS1,969,090 Mersereau et al. Aug. 7, 1934 2,046,180 Pfiasterer June 30,1936 2,367,723 Haines Jan. 23, 1945 2,492,398 Quinlan Dec. 27, 1949

